This application is based on application Nos. 10-133586 and 10-133587 filed in Japan, the contents of which is hereby incorporated by reference.
1. Field of the Invention
The present invention relates to a management unit transmitting data from an apparatus to a centralized management unit through a communication line, and to the centralized management unit.
2. Description of the Related Art
Conventionally, a method of centralized processing and management in which management data of a plurality of copying machines are transmitted to a single central processing unit and batch-processed and managed by the central processing unit has been known from, for example, U.S. Pat. No. 4,583,834. Further, an apparatus for managing a plurality of copying machines in which management data of each of the copying machines are transmitted to a single central control unit through respective terminal units to be processed by the central control unit has been known from U.S. Pat. No. 4,583,834.
The conventional central processing unit or the central management unit does not allow a plurality of copying machine management units transmitting data in accordance with different communication methods to be connected to one centralized management unit for the management of each copying machine. Here, different communication methods refer to CCITT method and Bell method, for example.
Among the various communication systems, some communication protocols are determined by standard. However, in most cases, the communication methods are not common or compatible. Therefore, when two different systems are to be integrated and managed, different communication protocols must be applied to one system mixedly. Consequently, it has been necessary to provide communication units in compliance with respective communication protocols separately, resulting in increased cost. This is a significant disadvantage for the user.
When communication protocols having similarities to some extent are to be integrated, it is possible to automatically determine the difference of communication protocol at the start of a communication session and to switch the communication protocol thereafter. Such an approach, however, requires much time for switching between the communication protocols, resulting in an overhead at that portion, and reliability in switching may possibly be degraded. Further, automatic determination is not available if the communication protocols do not have any similarities therebetween.
Therefore, an object of the present invention is to facilitate management of a plurality of systems employing different communication protocols by integrating the plurality of systems and using one centralized management unit and communication units connected thereto.
Another object of the present invention is to enable management of a plurality of management units transmitting data in compliance with difference communication methods through the use of one centralized management unit.
The management unit in accordance with the present invention, therefore, includes: a data collector collecting various data of connected units; a connector to a communication line; and a communicator transmitting the various data to a centralized management unit through the communication line. The management unit has at least two data communication processing methods, and includes a timer, a comparator comparing the time measured by the timer with a time band set in advance in the centralized management unit, and a communication process initiator responsive to the result of comparison by the comparator, for selecting the data communication processing method and initiating a communication process. The management unit or the centralized management unit initiate (switches) an appropriate communication processing method, and performs data communication in compliance with the communication process method.
Therefore, it becomes unnecessary to provide communication terminal units by the number of the communication processing methods, and lower efficiency and lower reliability resulting from the procedure of determining the communication protocol can be avoided.
If it is determined by the comparator that the time band allows no communication process in any data communication processing method, the method is switched to that data communication processing method which is set for a time band of a near future, and the control enters a communication standby state. The management unit further includes a detector for detecting any trouble or a warning state which requires a warning of the unit, and a transmission initiator for initiating a transmission process at the time of detection, and based on the result of comparison by the comparator, communication process is performed after standby until that time band which allows communication. The time band set in advance in the centralized management unit is input and stored from the management unit through the communication line.
According to another aspect of the present invention, the centralized management unit includes a communicator receiving, from a management unit including a collector collecting various data of connected units and a connector to a communication line, the various data through the communication line. The centralized management unit has at least two data communication processing methods, and includes a timer, a comparator comparing the time measured by the timer with a time band set in advance and a communication initiator responsive to the results of comparison by the comparator for selecting the data communication processing method and initiating a communication process. The time band set in advance in the centralized management unit is stored from the management unit through the communication line. Further the allocation of time bands to the communication processing methods is adjusted in accordance with the number of communication processing methods used by the management units for communication.
According to a further aspect of the present invention, units connected to a management unit are controlled by the centralized management unit by receiving various data through a communication line and a terminal adapter from the management unit including a collector for collecting various data of connected units and a connector to the communication line. The centralized management unit includes a terminal adapter allowing reception from a plurality of different management units having different communication methods to be used for transmitting various data over the communication line, and a setter for setting the communication method of the terminal adapter in accordance with a prescribed priority. Th centralized management unit further includes a switch for switching, when reception of the various data in accordance with the communication method set by the setter fails, the communication method to one having lower priority.
The centralized management unit sets the terminal adapter first to a communication method of a first or highest priority (for example, CCITT method), and stands by for the transmission of data from the management unit. When the terminal adapter succeeds in receiving data at the start of transmission of the data to the centralized management unit, data transmitted continuously in compliance with the communication method is received continuously. When the terminal adapter fails to receive the data in compliance with the communication method of the first priority, the communication method of the terminal adapter is switched to the communication method of a second priority (Bell method), and the adapter again stands by for the transmission of data from the management unit. Thereafter, the communication method of the terminal adapter is switched in accordance with the priority until the data is received successfully.
Accordingly, it becomes possible to manage by a single centralized management unit, a plurality of different management units transmitting data in accordance with different communication methods.
In a further aspect of the present invention, a unit management system includes a plurality of management units provided with a collector for collecting various data of connected units and a connector to a communication line, and a centralized management unit managing the units connected to the management units by receiving various data from each of the management units through the communication line and a terminal adapter. The centralized management unit includes a terminal adapter allowing reception from a plurality of different management units having different communication methods to be used for transmitting various data through the communication line, and a setter for setting the communication method of the terminal adapter in accordance with a prescribed priority. Preferably, the centralized management unit further includes a switch for switching, when reception of the various data in accordance with the communication method set by the setter fails, the communication method to one having lower priority.
In the centralized management unit and the unit management system, the units are managed in accordance with respective communication methods, based on the various data received.
In the centralized management unit and the unit management system, when data reception in accordance with a communication method of which priority is not the highest is successful, the communication method is returned to the one having the highest priority.
Further, in the centralized management unit and the unit management system, the communication method of the terminal adapter is set in accordance with the number of management units using respective communication methods for transmitting various data, that is, the communication method employed by larger number of management units is set with higher preference.
When data reception in compliance with a communication method of which priority for the terminal adapter is not the highest is successful, the communication method may be switched to the one having the highest priority, or the communication method of the terminal adapter is set in accordance with the number of management units in compliance with respective communication methods for transmitting various data. Therefore, possibility of completing data transmission at one time without the necessity of re-transmission of the data from the management unit becomes higher.
The foregoing and other objects, features, aspects and advantages of the present invention will become more apparent from the following detailed description of the present invention when taken in conjunction with the accompanying drawings.